Search results for "Visual Processing"

Near- and Far-Surround Suppression in Human Motion Discrimination.

2018

The spatial context has strong effects on visual processing. Psychophysics and modeling studies have provided evidence that the surround context can systematically modulate the perception of center stimuli. For motion direction, these center-surround interactions are considered to come from spatio-directional interactions between direction of motion tuned neurons, which are attributed to the middle temporal (MT) area. Here, we investigated through psychophysics experiments on human subjects changes with spatial separation in center-surround inhibition and motion direction interactions. Center-surround motion repulsion effects were measured under near-and far-surround conditions. Using a sim…

Honeybees can recognise images of complex natural scenes for use as potential landmarks

2008

SUMMARY The ability to navigate long distances to find rewarding flowers and return home is a key factor in the survival of honeybees (Apis mellifera). To reliably perform this task, bees combine both odometric and landmark cues,which potentially creates a dilemma since environments rich in odometric cues might be poor in salient landmark cues, and vice versa. In the present study, honeybees were provided with differential conditioning to images of complex natural scenes, in order to determine if they could reliably learn to discriminate between very similar scenes, and to recognise a learnt scene from a novel distractor scene. Choices made by individual bees were modelled with signal detec…

Project DyAdd: Non-linguistic Theories of Dyslexia Predict Intelligence

2020

Two themes have puzzled the research on developmental and learning disorders for decades. First, some of the risk and protective factors behind developmental challenges are suggested to be shared and some are suggested to be specific for a given condition. Second, language-based learning difficulties like dyslexia are suggested to result from or correlate with non-linguistic aspects of information processing as well. In the current study, we investigated how adults with developmental dyslexia or ADHD as well as healthy controls cluster across various dimensions designed to tap the prominent non-linguistic theories of dyslexia. Participants were 18–55-year-old adults with dyslexia (n = 36), …

Editorial: Face Perception across the Life-Span

2016

Effect of specialized applications on the visual functions of amblyopic eye in Latvian children

2021

The classical treatment option of amblyopia is occlusions of non-amblyopic eye. The newest methods involve specialized computer and phone games, applications that involve both eyes in visual processing during treatment as well as stimulate binocularity. The aim of the work was to assess the efficiency of specialized phone application ‘Duovision’ in the treatment of amblyopia in preschool-age children. There were 30 participants (5-8 years old): 16 participants had occlusion therapy; 14 participants played the specialized phone application Duovision®. The visual acuity of amblyopic eye, as well as stereopsis was evaluated at near and far distances before the treatment, 2 and 4 months after t…

Processing of audiovisual associations in the human brain: dependency on expectations and rule complexity

2012

In order to respond to environmental changes appropriately, the human brain must not only be able to detect environmental changes but also to form expectations of forthcoming events. The events in the external environment often have a number of multisensory features such as pitch and form. For integrated percepts of objects and events, crossmodal processing, and crossmodally induced expectations of forthcoming events are needed. The aim of the present study was to determine whether the expectations created by visual stimuli can modulate the deviance detection in the auditory modality, as reflected by auditory event-related potentials (ERPs). Additionally, it was studied whether the complexi…

Do categorical representations modulate early automatic visual processing? A visual mismatch-negativity study.

2021

Perceptual categorization is an important cognitive function. In the auditory domain, categorization already occurs within the first 200 ms of information processing, as indexed by the mismatch negativity. Here, we assessed the characteristics of the visual mismatch negativity (vMMN) elicited during the categorization of previously unknown visual stimuli. To examine this, we used five-dot patterns with characteristics that allow for the formation of categories through rotation and reflection but not through other physical properties. To assess whether or not between-category and within-category vMMN differ in amplitude, the data was analyzed with the Bayesian approach. We observed that both…

Panel Summary: Plasticity and Reconfigurability in Sensory Systems

1997

Natural neural network are highly plastic in structure and function and may adapt to long lasting environmental changes. Plasticity and adaptation are not confined to lower level of processing, or to lower vertebrates, but also at the higher levels of visual processing in higher vertebrates are highly dynamic and perform considerable spatial integration. There are numerous influences that play a role in the functional architecture of the retina and the, cortex, the dynamics of the outside environment, the context within which a feature is presented, the history of previous visual stimulation and attention or expectation. The brief report on the visual system is integrated by the report of G…

Color stabilizes textbook visual processing

2011

We report that pages with color illustrations elicit more homogeneous duration of fixations in 12 elementary school children. For six first graders, we compared the reading of the color cover and a greyscale illustrated text page of an abcbook. For six second grade pupils, we demonstrated a color and a greyscale fairytale book page. The fixations we recorded are concordant with the duration for preschoolers reported elsewhere. Average duration of fixations on a page with color elements are shorter than on greyscale ones, 425 (SE=13.4) and 461 (18.3) ms, respectively. The correlation analysis lends support that a color page is processed differently than its greyscale version. Fixation durati…

Attention Direction in Static and Animated Diagrams

2010

Two key requirements for comprehending a diagram are to parse it into appropriate components and to establish relevant relationships between those components. These requirements can be particularly demanding when the diagram is complex and the viewers are novices in the depicted domain. Lack of domain-specific knowledge for top-down guidance of visual attention prejudices novices' extraction of task-relevant information. Static diagrams designed for novices often include visual cues intended to improve such information extraction. However, because current approaches to cueing tend to be largely intuitive, their effectiveness can be questionable. Further, animated diagrams with their percept…